The vascular anatomy of the anterior lobe (AL) of 182 previously injected human pituitary glands was examined. Three different techniques of injection using India ink and acrylic paints were performed to establish a direct arterial supply to the AL. In 81% of the cases, end-arteries were found in the AL. Their participation in the vascularization of the adenohypophysis is variable from a small subcapsular area to almost the entire lateral parts of the AL. Arteries playing some role in the perfusion of the AL are subdivided into infra- and supradiaphragmatic, according to their topography in relation to the diaphragma sellae. Evidence of the presence of end-arteries in the AL is in disagreement with the generally accepted concept of a purely portal supply to this part of the pituitary gland.